JonC

Hi, I'm new here but just bought a 1993 Grand Cherokee with 4.0 and auto in it. It has been sitting for 7 years, got it home put new gas in it and changed oil. I put in a fresh battery and it turned over about 5 times and started up perfectly. I let it run for about 15 minutes and shut it off to unhook straps holding it on my car trailer. Then it would not start again. No spark and no fuel. I operated the fuel pump relay by hand and could hear the fuel pump run. Any opinions??

JonC

I checked other forums and ended up changing Crank sensor, Cam sensor and a good junkyard computer. Now the engine starts and only runs for 2-3 seconds. And the interior lights stay on. Any help this time????

Bustedback

Your junkyard PCM may be in theft mode. Put the original PCM back in and see what happens.

hitalonit

x2.... it also sounds like starting up only for 15 min u rattled all the gunkl around for just enough and now something maybe clogged

JonC

I put in the crank sensor first, nothing. Then I put in the cam sensor, nothing. Then I put in the PCM and now have the run for 2 seconds and the interior light issue. This vehicle doesn't have a security module, can the new PCM still be in theft mode?? If so, how do I change it?

JonC

OK, I read elsewhere that I can't use a PCM from a vehicle with a security system in a vehicle without one. My new junkyard and the original have the same part number on them. Is it possible that one could be programmed for security and the other not? Can it be flashed, jumped, modified or do I need a different one?

matt_101

I got a computer off this guy on ebay..... he programs them for your VIN. plugged mine in and it work perfectly.

link: http://myworld.ebay.ca/allcomputerresources/

Good luck.

JonC

Can a dealer do this???

matt_101

i doubt it..... they'll probably want to sell you a new one.

worth a shot though, bring the computer in and see if they'll do it.

JonC

Thanks for the info, is there a way to do it myself such as ground a certain pin on the PCM or something else?

JonC

Now I've been told that the new PCM has contaminated the BCM into thinking theft mode and I need to replace both now. Dealer says he can't program the PCM. Any truth to this???

JonC

I think I just found out there is no BCM in a 1993. I need to get this thing going cheap, please any help.

JonC

I had the right ECM but it apparently got told it had anti theft. I put in another junkyard one and it now runs. But I still have the dome light always on problem, can anyone help with that??

Bustedback

Move the dimmer switch to the left.

JonC

I've done all those things, dash switch, door switches, rear hatch etc. When I turn the key on to the run position the lights go out. If I start the truck the lights go out. I turn off the engine and take the key out and it stays on.